Water-heating apparatus



Oct. 28 1924.

- 1,513,449 J. s. ERICKSEN WATER HEATING APPARATUS Filed Sept. 5, 1922 4 Sheets-Sheet 1 Oct. 28 1924. v 1,513,449

J. s. 'ERIcKsEN WATER HEATING APPARATUS Filed Spt. 5, 1922 4 Shets-Sheet 2 Oct. 28 1924.

v J. S. ERICKSEN 1 WATER HEATING APPARATUS Filed Sept. 5, 1922 4 Sheets-Sheet 5 F m d llule n a M 5 W Oct. 28 1924.v

J. s. ERICK SEN WATER HEATING APPARATUS 4 Sheets-Sheet 4 Filed Sept. 5, 1922 Patented Oct. 28, 1924.

' JACOB S. ERICKSEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO FERGUSON AND LANGE FOUNDRY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION "OF ILLINOIS.

WATER-HEATING APPARATUS.

Application ma' September 5, 1922. Serial No. 586,188.

To all whom it may concern:

a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in ater-Heating Apparatus, of which the following is a speclfication.

My invention relates to apparatus for heating water, more particularly to an apparatus adapted to be used in? con unction with the heating boiler of a home, apartment building, hotel, institution or the like, and to furnish a supply of hot water. 0

The primary object of my invention is the provision of water heating apparatus of the general type referred to which Wlll be relatively simple inconstruction, easy and inexpensive to install, efficient in operation, economical in fuel consumption, require but little attention to operate, inexpensive to maintain in operation, will reduce fire hazards, and which will serve to maintain a supply 'of hot water of substantially uniform temperature for-wash basins or other fixtures available for immediate use; and,to

' this end, the inventionpreferably contemplates the provision-bf a storage tank connected with a source'of cold water supply, a water 'cheater' adapted; to be positioned in a receptacle containing a heatingmediu n, for example, a hot water circulatin boiler, a steam generating b'oiler, or the 11 e, in such inann'er' that the heater will be subject to the heating action of the medium, a'circulating system so connected with the storage tank and the heater that cold water will flow from-the lower portion of'the-tank to the heater where it will be heated and then flow to=andabe discharged into the upper portion of the tank, and a hot water circulating consumption system so connected with the storage" .t'ank and they first mentioned system that ihot water will flow continuously from the storage tank through the consumption system and be returned to the water heater. 5 Water heating apparatuses for furnishing hotz'water to apartment buildings, hotels, institutions and other buildings where a considerable quantity of hot water is used are ordinarily specially designed for each building, which materially increases the cost of :tliexapparatus and its installation. It is a further object of my invention to provideapparatus for this purpose the construction of which will be standardized to a very large Be it known that I, JAcoB S. ERi'oKsEN,

extent so that the apparatus may be made in various sizes to suit the requirements of the diiferent buildings and the various parts comprising the apparatus, ma be manufactured in quantities and carried in stock, whereby the cost and the installation of the apparatus will be reduced to a minimum. With this in view, my invention preferably contemplates providing, in addition to the usual partscomprising the apparatus, an independent receptacle in which one or more water heaters connected to the apparatus mentioned may be installed, saidirece tacle. being so connected with the heating oiler that the heating medium may circulate from the boiler, through the receptacle and back to the boiler. This feature of my invention is particularly advantageous where the heating boiler is of the sectional type and it is impractical to install the water heater directly in the boiler. In the case last mentioned, the various sections of the heating boiler adjacent their upper ends are connected by a system of pipes with the receptacle containing the Water heater and the heating medium is returned from said receptacle to the boiler in substantially the same manner as the feed water flows into the boiler, and the efficiency of the heating boiler is materially increase It is a further object of my invention to connect the pipes comprising the hot Water circulating consumption system with the storage tank and the circulating system connecting the storage tank and the heater in such manner that the formation of air pockets in the last mentioned circulating system will be prevented and a continuous flow of water in this system insured.

k A further object of my invention is the provision of means whereby the storage v tank will not be by-passed when hot water is drawn from the consumption circulating system; and, to this end, a very sensitive check valve is provided in the return pipe of the consumption circulating system which is so constructed that, upon reversalof the flow of water in said pipe, said valve will instantly close, and any Water taken from the consumption system will be drawn directly from the storage tank.

A further object of my invention is the provision of a system of piping connecting the storage tank with the Water heater so arranged that the pipes may easily be cleaned and kept free of mud or sediment. To this end, thesystem is so arranged that most of the mud or sediment in the water will not be permitted to get into the entire system aforesaid but will be confined to certain portions thereof which are constructed in such manner that the mud or sediment may be easily removed, and the remaining portions of the system are so arranged that the mud or sediment which is deposited in the water heater and the pipes leading to and from the heatermay be easily flushed out.

The invention consists in the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects and such other objects as will appear from the fol- ,lowing description of certain preferred embodiments illustrated in the accompanying drawings, Wherein Fig. 1 is a diagrammatic view of water heating apparatus embodying the principles of my invention Fig. 2 is a diagrammatic view of a portion of the apparatus and illustrating a modified arrangement whereby the formation of air ckets in the circulating system connecting the storage tank with the water heater will be prevented;

Fig. 3 is a diagrammatic view of water heating apparatus embodying the principles of my invention and connected to a boiler of the sectional type;

Fig. 4% is a side elevational view, on an enlarged scale, of my preferred form of water heater installed in a heating boiler of ordinary construction, certain parts being broken away to show the internal construction;

Fig. 5 is a longitudinal sectional view, on a further enlarged scale, of the water heater;

Fig. 6 is a sectional view, on an enlarged scale, of a portion of the apparatus illustrating the preferred arrangement whereby the formation of air pockets'in the circulating system connecting the storage tank with the water heater will be prevented;

Fig. 7 is a longitudinal sectional view,

on an enlarged scale, of the preferred form of check valve employed inthe return pipe of the consumption circulating system;

Fig. 8 is a transverse sectional'view taken on the line 8-8 of Fig. 7;

Fig. 9 is a sectional view of. a modified form of check valve which may be employed in the return pipeof the consumption circulating system; and

Fig. 10 is a sectional view taken on the line 10-10 of Fig. 9.

Like characters of reference designate like parts in the several views.

Referring now to the drawings, and parneiaeee ticularlyto the diagram shown in Fig. 1 thereof, it will be seen that the apparatus includes a storage tank 12 supplied with cold water by means of a pipe 13 l eading from a source of supply under pressure and which terminates a short distance above the bottom of the tank. The tank 12 is connected with a water heater, designated generally by the reference character 1% and positioned in .the heating boiler 15, by a plurality of pipes, including a substantially vertically disposed stand pipe 16 the upper end of which projects upwardly through and terminates a substantial distance above the bottom of the tank and the lower end of which is provided with a shut-off cock 17. The pipe 16 is provided with a fitting 18 from one side of which extends a horizontal pipe 19 connected by a T-shaped fitting 20 with a relatively short pipe 21. The pipe 21 is connected by means of a T-shaped fitting 22 with a horizontally extending pipe 23. A T-shaped fitting 24 is provided on one end of the pipe'23 and is connected by a pipe 25 with the water heater. The pipe 26 is connected at its lower end to the water heater and at its upper end to a "n"- shaped fitting 27. Ahorizontally extendmg pipe 28 is connected at one end to the fitting 27 and at the other end to a T-shaped .pipes 35 with the pipe 36 which extends through the fitting 29, the pipe 30 and into the storage tank 12, the lower end'of said pipe 36 extending a substantial distance below the level at which the pipe 30 discharges into the tank. A. recording thermometer 37 may be connected in the hot water consumption system if desired. A check valve, designated generally by the reference character 38, is preferably provided in the return pipe 33. A cold water supply pipe 39 ordinaril extends alongside the pipe 31 but, as thlspipe forms no part of the apparatus, its various connections and outlets have not been illustrated.

The water heater is shown in detail in inlet pipe 25. One wall of the chamber 43.

is provided/with an opening also threaded fonthe reception of the hot water discharge pipe 26. The inner side of the head 40'is provided with a flange 46 adapted to be placed against the face of the boiler, see Fig. 4, and to be secured thereto by a plurality of cap screws. The flange 46 is provided with an opening 47 and is threaded for the reception of a relatively large pipe 48, which is formed of a non-corrosive substance the heat conductivity of which is relatively high, for example, copper. The head of the heater is provided with an opening 49 so that communication is established between the chamber 43 and the pipe 48. The inner end of the pipe 48 is closed by any suitable means, for-example, a cap 50. The I partition 41 is provided with an opening 51 which is substantially concentrically disposed with respect to the openings 49 and 47, and the pipe 48. The outer end of a relatively small pipe 52 is placed in the opening 51 and said pipe is secured in the partition 41 in any desired manner, for example, by turning the outer end of the pipe over the adjacent portion of the partition. The pipe 52 extends inwardly into the pipe 48, the inner end of said pipe 52 being left open and terminating somewhat short of the end of the "pipe 48. The pipe 52 is also preferably formedof a non-corrosive substance the heat conductivity of which is relatively high, and, as the walls thereof are quite thin, the pipe is preferably formed of brass to ive it the desired strength. The wall of t e chamber 42 opposite the partition 41 is provided with an opening 53 threaded for the reception of a plug 54.

The cold water flows from the pipe 13 under pressure into the lower portion of the stora e tank, flowing therefrom into the charm er 42 of the water heater, thence through the small pipe 52'and is discharged into the inner end of the large pipe 48 where its direction of flow is reversed, the water then flowing out of the pipe 48 into the chamber 43. The course of the water through the heater is indicated by the several arrows.

in Fig. 5. As the pipe 48 of the heater is sub'ect to the heating action of the heating medium surrounding it, said pipe is heated, and, consequently, the temperature of the water while passing through said pipe will be raised very considerably. The hot water flowing in the pipe 48 transmits heat to the pipe 52 and said last mentioned pipe is heated to a considerable extent. By this arrangement the water is gradually heated as it enters the pipe 52 and is subject to the greatest degree 0t heat while through the pipe 48. Since the heat conduc-. tivity of the pipes 48 and 52 is relatively high, the efficiency of the heater is also high.

The hot water flows through the pipes 26,

passing 28 and 30 and is discharged into the upper portion of the storage tank. The hot water accumulates in the upper portion of the storage tank and continually circulates through the hot water circulating consumpwill be noted that the pipe 36 is provided with a port 36 which is so located that communication is established between said pipe and the upper portion of the chamber 29 provided in the fitting 29. This arrangement prevents a column of air being trapped in the pipe 30, fitting 29 and pipe 28, because in drawing water from the pipe 31 any air present in the pipe 30, fitting 29 or pipe 28 will be drawn through the port 36*, thereby insuring free circulation of hot water through the pipes 28 and 30. The same results may be obtained by the arrangement shown in Fig. 2 of the drawing wherein thelower end of the pipe 31 is connected to a fitting 55, the latter being connected by a pipe 56 with the storage tank and by a pipe 57 Wltlltllfi fitting 29. The parts are so arranged that the pointof connection between the pipe 57 and the pipe 31 is not substantially lower than the point of connection between the pipe 57 and the fitting 29. WVith this arrangement, when water is drawn from the pip 31, any air that may be present in the pipe 28, fitting 29 or pipe 30 will be drawn out through the pipe 57 and into the pipe 31.

When hot water is drawn from the pipe 31 the check valve 38 in return pipe 33 prevents the storage tank from being bypassed which might occur if the check valve 38 were not provided. With the check valve 38 in the pipe 33 any-reverse flow of water in pipe 33 will be checked. The check valve employed in the return pipe 33 must he very sensitive and is preferably either of the form shown in Figs. 7 and 8 or of the form shown in Figs. 9 and 10.

Referring to Figs. 7 and 8, the body por tion of the check valve consists of a standard T-shaped pipe fitting 58 provided with the usual openings 59, 60 and 61. A bushing 62 provided with external and internal threads is inserted in the opening 60, one portion of the pipe 33 being threaded into the bushing and the other portion of said pipe being inserted into the opening 61. The opening 59 is closed by the' screw plug 63. A ballifioat 64 is so positioned with in the body 58 that water may flow in the direction indicated by the arrow, see Fig.

7, but is checked whenever the flow is reversed. Movement ozt the float (it is restricted by a plurality of prongs 65 which project from the inner side of the bushing 62, the free ends of said prongs be ing bent over substantially as shown in Fig. 7 so as to engage the float. This type of check valve is inexpensive to manufac ture and is extremely sensitive in operation.

The check valve shown in Figs. 9 and 10 comprises a hollow body member 66 provided with openings 67 and 68 into which the ends of the return pipe 33 -may be threaded. The body is provided with a seat 69, a gate member 70 being pivoted at 71 to the valve body so that it may freely swing against the seat 69. The gate may be in serted into the body through an opening 72 which is normally closed by a cap member 73. The action of this type of valve is extremely sensitive, the flow of water in a direction opposite to the normal flow as indicated by the arrow shown in Fig. 10 will cause the gate to swing instantly till against the seat 69.

The manner in which my apparatus may be standardized is illustrated diagraminatically in Fig. 3 wherein it will be noted that the water heater is installed in a receptacle 74 which may be of anydesirecl construction. The receptacle 74: is shown as operatively connected with a heating boiler 75, of the sectional type. The several sections of the boiler are each-connected by a pipe 76 with the'receptacle 74: the pipes 7 6 preferably being connected to'the upper portions of the several boiler sections which permits the heating medium at its highest temperature to flow from the boiler sections into the receptacle 7%. The heating medium is returned to the boiler by a pipe 7? in substantially the same manner as the feed water is supplied to the boiler. It is impractical to install the water heater directly in a boiler of the sectional type but, when the receptacle 74 is provided adjacent the boiler, it is a comparatively simple matter to connect the respective boiler sections with the receptacle. Connecting the receptacle Tswith the upper portions of the respective boiler sections and returning the heating medium to the boiler as described greatly increases the circulation of the heat ing medium through the sections of the boiler and hence increases the efiiciency of the boiler. It will be obvious that the receptacle 74 may be readily installed in COD."

' nection with any type of boiler Apparatus embodying the principles of my invention may be made in various sizes toisuit the requirements of difierent build-' intense ings, and the various parts or me apparatus may be manufactured in quantities and carried in stock, thereby making it unnecessary to design specially the apparatus for each installation, With my apparatus the heat ing boiler is utilized to heat the necessary v amount of hot wamr required for consump tion and it is not necessary to provide a spe 'cial heater. in water heating systems com monly employed, particularly in large buildings, the vvater is ordinarily heated by a spe cial heater and, as the demand on such systerns are higher at certain times of the day 4 than at others for example, in the morning, the janitor will frequently force the heater to such an extent as to overheat it consider ably. Many fires have resulted directly from this cause. ll ith my apparatus no extra heater is provided and the lire hazard is considerably reduced.

'Heating 'the water for the consumption system b utilizing the heating boiler mate rially re uces the amount of fuel use-cl as it is considerably less expensive to the a little additional fuel into the heating boiler to compensate for the water heafting apparatus than it is to fire two independent boilers ln this same connection it is also to be noted that there is a considerable saving of the janitors time.

l/Vith my apparatus the water heater does not come into direct contact with the fire. The, alkalinous deposits in water are not freed unless the water reaches approximatefly the boiling point. The ordinary heating boilers usually carry a pressure considerably less than fifteen pounds and taking into consideration the transmimion losses, it has been found that the temperatureof the water in the water heater very rarely exceeds one hundred and ninety degrees, hence the alkali in the water is not freed. This is an important matter, as no scales or crusts are formed in the pipes of the. water heater and its eficiency is not impaired. The tempera-- ture of the water in the consumption system remains at substantially a uniform temperature'.

With proper care the apparatus will last as long as the heating boiler itself and requires no special attention except to flush out the sediment in the main circulating pipes occasionally. By connecting the pipe 16 with the storage tank in the manner heretofore described, a large portion of the sediment in the water will deposit in the bottom of the tank and not pass into the circulating pipes. The sediment deposited in the bottom of the tank may be flushed out of the tank by removing the plug 78. The pipe 16 acts. as a collector for a considerable part of the sediment in the water flowing from the tank to the water heater. tae cock 1? the sediment present in the pipe 16 may be readily fiiushed out. llt will be By opening 7 noted that the pipes comprising the circulating system connecting the water heater with the storage tank include a plurality of T-fit-tings and in the arrangement shown in Fig. l, for example, the fittings v18, 20, 34, 24 and 27 are provided with plugs 18*, 20 34, 24*, and 27 respectively. By removing any two of these plugs and attaching a hose connected with a source of water supply the sediment in the intermediate sections of pipe may be easily flushed out. The water heater also may be flushed out by removing the plug 54 and attaching the hose.

I do not intend to limit my invention to the details of construction, arrangements and devices shown and described except only in so far as certain of the appended claims are specifically so limited, as it will be obvious to those skilled in the art, that modifications may be made Without departing from the principles of my invention.

I claim: 7

1. In combination with a receptacle containing a heating medium, a water heater positioned in said receptacle insuch manner that it is subject to the heating action of said medium, a storage tank, water supply means for said heater, a pipe leading from said heater andarranged so that water flowing therein must discharge into the upper portion of said tank, and a hot water circulating system including a pipehavin controlled outlet means, said second-name pipe leading from the upper portion of said tank and having its intake 'end sufficiently remote from the discharge end of said firstnamed pipe that water flowing into said second-named pipe must be taken from the supply in said tank, and a return pipe leading from the discharge end of said secondnamed pipe back to said water supply means.

2. In combination with a receptacle containing a heating medium, a water. heater positioned in said receptacle in such manner that it is subject to the heating action of said medium, water supply means including a storage tank for said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, and a discharge pipe having controlled outlet means, said second-named pipe leadin from the upper portion of said tank an having its intake end sufliciently remote from the discharge end of said first-named pipe that water flowing into said second-named pipe must be taken from the supply in said tank.

3. In combination with a receptacle containing a heatin medium, a water heater positioned in sai receptacle in such manner that it is subject to the heating action of said medium, a storage tank connected to a source of water supply, a pipe leadin from the lower portion of said tank to said heater, a pipe leading from said, heater and arranged so that water flowing therein must discharge into the upper portion of said tank, and a hot water circulating system including a pipe having controlled outlet means, said third-named pipe leading from the upper portion of said tank and having its intake end sufiiciently remote from the discharge end of said second-named pipe that Water flowing into said third-named pipe must be taken from the supply in said tank, and a return pipe leading from the discharge end of said third-named pipe back to said heater.

4:. In combination With a sectional boiler adapted to generate a heating medium, a receptacle, conduit means leadlng from the upper portions of the respective boiler sec tions to said receptacle and so arranged that the heating medium may flow into said receptacle, means to return said medium to said boiler sections thereby establishing a circulatory system between said receptacle and said boiler sections, a water heater positioned in said receptacle in such manner that it is subject to theheating action of said medium, a storage tank, water supply means for said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, and a hot water circulating system including a pipe havin controlled outlet means, said second-name pipe leading from the upper portion of said tank and having its intake end sufiiciently remote from the discharge end of said firstnamed pipe that water flowing into said second named pipe must be taken from the supply in said tank, and areturn pipe leading from the discharge end of said secondnamed pipe back to said water supply means.

5. In combination with a sectional boiler adapted to generate. a heatin medium, a receptacle, conduit means leading from the upper portions of the respective boiler sections to said receptacle and so arranged that the heating medium may flow into said receptacle, means to return said medium to said boiler section's thereby establishing a circulatory system between said receptacle and said boiler sections, a water heater positioned in said receptacle in such manner that it is subject to the heating action of said medium, water supply, means including a storage tank for said heater, a pipe leading from said heater and arranged so that intake end sufficiently remote from the discharge end of said first-named pipe that .water flowing into said second named pipe must be taken from the supply in said tank.

6, in combination with a sectional boiler d ited to generate a heating medium, a receptacie, conduit means leading from the upper portions of the respective boiler sec- 'ons to said receptacle and so arranged that heating medium may flow into said receptacle, means to return said medium to said boiler sections thereby establishing a circulatory system between said receptacle and said boiler sections, a Water heat r positioned in said receptacle in such manner that it is subject to the heating action of said medium, a storage. tenk connected to source'oi water supply, a pipe leading from the lower portion of said tank to said heater, a pipe leading from said heater and urranged so that water flowing therein must discharge into the upper portion of seid tank, and a hot Water circulating system including a pipe having controlled outlet means, said thirdnamed pipeleading from the upper portion of said tank and having its intake end sufficiently remote from the discharge end of said secondnamed pipe that Water flowing into said third-named pipe must be telreniirom supply in said tank, and a, return pipe leading" from the discharge end of said thirdnamed pipe back to said heater,

'2, In combination with a receptacle con taining a heating medium, a Water heater positioned in said receptacle in such man nor that it is subject to the hen ting action of said medium, Water supply means in; cluding a storage tank for said heater, a pipe leading from said heater and arranged so that Water flowing therein must discharge into the upper portion of said tank, a hot Water circulating system including a pipe heving' controlled outlet means, saidseco-ndnamed pipe leading from the upper portion of said tank end havin its intake end smith-- ciently remote from the discharge end of said first-named pipe that Wafmr flowing into said second-named pipe must be taken from the supply'in said tunic, it return pipe leading from the discharge end of said sec-- ond-nanied pipe bacli to said Water supply means, and means comnninicetively connecting said first-named pipe with said second-- named pipe, for the purpose specifie 8. In combination with u receptacie con mining a heating medium, e Water heater positioned in said receptacle in such manner that it is subject to the beating action oi said medium, Water supply means including a storage tank for said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, e hot Water circulating system including a pipe having controlled outlet means, said second-named pipe leading from the upper portion oi said tank and having its intake end su'fiii silently remote from the discharge oi;

said medium, Water supply means including a storage tank for said heater, a pipe lead ing from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, a chambered fitting provided in said pipe, 2, hot Water circulating system including a pipe having cont-rolled outlet means, said second-named pipe extending through said fitting and that portion oi said, first-named pipe between said fitting and said tank and having its intelte end suiiiciently remote from the discharge end of said first-named pipe that water flowing into said second-named pipe must be taken from the supply in said tank, and a return pipe leading from said secondnamed pipe back to said Water supply means, said secondmamed pipe havin a port leading into the upper portion 0 the chamber in said fitting, for the purpose specified.

10. In combination with a receptacle containinp; a heating medium, a Water heater positioned in said receptacle in such manner that it is subject to the heating action of said medium, a storage tank connected to a source of water supply, a pipe leading from the lower portion of said tank to said heater, a pipe lezuiinp;- from said heater and discharging; into the top of said tank, a chenr ibered fitting provided in said second inentioned pipe, and a hot Water circulating system including a pipe having-.outlet means and a return pipe leading from said third mentioned pipe back to said heater, the

lower portion of said third mentioned pipe 4 extending through said fitting and that por tion of said second mentioned pipe between said fitting and said tank and terminating sutiiciently below the point of discharge of said second mentioned pipe into said tank so that Water drawn from said third men tioned pipe will flow from the tank and not directly from said second mentioned pipe, said third mentioned pipe having" a port leading into the upper portion of the chamber in said fitting, for the purpose specified,

11.. llnxcombination with a receptacle containing a heating medium,a water heater positioned in said receptacle in such manner that it is subject to the heating ection of said medic-am, Water supply means including a storage tank for said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the.up--

per portion of said tank, and a hot water circulating system including a pipe having controlled outlet means, said second-named pipe leadingfrom the upper portion of said tank and having its intake end sufiiciently remote from the discharge end of said firstnamed pipe that Water flowing into said second-named pipe must be taken from the supply in said tank, a return pipe leading from the discharge end of said second-named pipe back to said water supply means, and a check valve in said return pipe, for the purpose specified.

12. In combination with a receptacle containing a heating medium, a water heater positioned in said receptacle in such manner that it is subject to the heating action of said medium, water supply means including a storage tank for said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, a hot water circulating systemincluding a pipe having controlled outlet means, said second-named pipe leading from the upper portion of said tank and having its intake end sufficiently remote from the discharge end of said first-named pipe that water flowing into said secondnamed pipe must be taken from the supply in said tank, a return ipe leading from the discharge end of said second-named pipe back to said water supply means, means communicat-ively connecting said first-named pipe with said second-named pipe, a return pipe leading from the discharge end of said second-named pipe back to said water supply means, and a check valve in said return pipe, for the purpose specified.

13. In combination withla receptacle containing a heating medium, a water heater positioned in said receptacle in such manner that it is subject to the heating action of said medium, water supp-l means including a storage tank for said eater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, a hot water circulating system including a pipe having controlled outlet means, said second-named pipe leading from the upper portion of said tank and having its intake en ufliciently remote from thefdischarge end of said first-named pipe that water flowing into said secondnamed pipe must betaken from the supply in said tank, a return pipe leading from the discharge end of said second-named pipe back to said water supply means, means oommunicatively connecting said first-named pipe at substantially its highest point with said second-named pipe at a point not substantiallyg lower than said first-named point, a return pipe leading from the discharge end that it is subject to the heating action of said medium, water supply means including a storage tank for said heater, a substantially vertically disposed discharge pipe extending upwardly through and having its intake end a substantial distance above the bottom of said tank, controlled outlet means in the lower end of said discharge pipe, a pipe connecting said heater with said discharge pipe at a point substantially above said outlet means, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, and a hot water circulating system including a pipe having controlled outlet means, said fourth-named pipe leading from the upper portion of said tank and having its intake end sufficiently remote from the discharge end of said third-named pipe that water flowing into said fourth-named pipe must be taken from the supply in said tank, and a. return pipe leading from the discharge end of said fourth-named pipe back to said water supply means.

15. In combination with a receptacle containing a-heating medium, a water heater positioned in said receptacle insuch manner that it is subject to the heating action of said medium, Water supply means including a storage tank, a pipe connecting said supply means with said heater, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, said respective pipes having openings located at various points, screw plugs normally closing said respective openings whereby upon removal of the plugs, hose or pipes connected with a source of water supply may be temporarily attached and the sediment in said pi'pes flushed out, and a hot Water circulating system, including a pipe having controlled outlet means, said third-named pipe leading from the upper portion of said tank and having its intake end sufficiently remote from the discharge end of said secondnamed pipe that water flowing into said third-named pipe must be taken from the supply in said tank, and a return pipe leading from thedischa-rge end of said thirdnamed pipe back to said first-named water supply means. 7

16. In combination with a receptacle con-- ly through and having its intake end a sub stantial distance above the bottom of said tank, controlled outlet means in the lower end of said discharge pipe, apipe connect ing said heater with said discharge pipe at a point substantially above said outletmeans, a pipe leading from said heater and arranged so that water flowing therein must discharge into the upper portion of said tank, said second and third-named pipes having openings located at various points, screw plugs normally closing said respective openings whereby upon removal of the plugs, hose or pipes connected with a source or water supply may be temporarily rename JACUB S. ERICKSEN. 

